How much does it cost to fix Saunier Duval error code E20?

Typical repair cost for the Saunier Duval E20 fault is £250-450 including labour.

E20 High

Saunier Duval E20 Fault Code

Q: What does the Saunier Duval E20 fault code mean?

Your boiler has developed a communication error because two of its internal computer chips are not recognising each other correctly, preventing the system from operating.

The Saunier Duval E20 fault code means: your boiler has developed a communication error because two of its internal computer chips are not recognising each other correctly, preventing the system from operating.. It appears on 4 Saunier Duval models in our database.

Technical description: Interface PCB incompatible with main PCB

Typical repair cost £250-450 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Saunier Duval models that show the E20 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Saunier Duval E20 fault code information on this page is sourced and cross-checked against the official Saunier Duval service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026